1. Technical Field
The present invention relates to an electrode for a fuel cell, and a membrane-electrode assembly and a fuel cell system including the same. More particularly, the present invention relates to an electrode for a fuel cell which improves electrical conductivity, which has improved catalyst activity, and which provides a high power membrane-electrode assembly and fuel cell system.
2. Related Art
A fuel cell is a power generation system for producing electrical energy through an electrochemical redox reaction of an oxidant and a fuel such as hydrogen, or a hydrocarbon-based material such as methanol, ethanol, natural gas, and the like. Such a fuel cell is a clean energy source which may replace fossil fuels, and includes a stack composed of unit cells and produces various ranges of power output. Since it has a four to ten times higher energy density than a small lithium battery, it has been highlighted as a small portable power source.
Representative exemplary fuel cells include a polymer electrolyte membrane fuel cell (PEMFC) and a direct oxidation fuel cell (DOFC). The direct oxidation fuel cell includes a direct methanol fuel cell which uses methanol as a fuel.
The polymer electrolyte fuel cell has the advantage of high energy density and high power, but it also has problems in that there is a need to carefully handle hydrogen gas and a requirement for accessory facilities such as a fuel reforming processor for reforming methane or methanol, natural gas, and the like in order to produce hydrogen as the fuel gas.
Conversely, the direct oxidation fuel cell has an energy density lower than that of the gas-type fuel cell, but it has the advantages of easy handling of the liquid-type fuel, a low operation temperature, and no need for additional fuel reforming processors. Therefore, it has been acknowledged as an appropriate system for a portable power source for small and common electrical equipment.